Thread: Frontend public network re-configuration

Hi,

I need to reconfigure my public Frontend's network. I know that many networkjing information is spreaded in kusudb.

Is it possible to do this on a running system? Are there any tools to do this automatically by just providing the new network parameters?

Thanks in advance,

Martin Farias

Hi,

You should probably re-install with DHCP set for your public interface.

It is possible for you to reconfigure your networks manually through /etc/sysconfig/networks and then bring the changes to kusudb through netedit. But, your configuration for other services will then be out of sync. You would then have to manually update those or use the genconfig plaugins where applicable. For example: /etc/hosts, apache configuration

Hi kunalc,

Yes, I know that if I change the network configuration then kusudb won't reflect those changes and everything might just break.

I was asking if is there a method or just a checklist/tutorial that helps reconfigure my network settings to keep integrity in the whole system, cause if I start editing here and there I am sure I will miss some files and the integrity will be lost.

Thanks again

martin

Hi Martin,

At present there is no method to make changes to network configuration and update the system accordingly. I could not find any material to help guide you either. I would still suggest a re-install if it is possible.

In case you want to attempt a manual reconfiguration, please proceed with caution since there is no guarantee for success. And, there is a chance of ending up needing a fix for your new configuration over and above your reconfiguration issues.

Here are a few general guidelines you can observe:

1. Please save all system and kusu configuration files before editing them. You could possibly revert to your existing configuration just by replacing any files you break in this way.

2. Back up your nodegroups and shutdown your compute nodes.

3. Save a dump of kusudb, and any other databases you may have from kits or other software you may have installed.

4.a. Whenever possible, try to use the kusurc scripts to reconfigure and restart services, instead of doing so manually.

4.b. When reconfiguring services manualy, try to use the genconfig plugins after making changes to the kusudb to generate configuration files, rather than editing config files by hand.

Follow the general steps below to change your public network:
0. Back up everything....

1. Bring down your public interface and reconfigure /etc/sysconfig/network-scripts/<> file to manually reconfigure your network. Then, restart your public interface and test it out manually.

2. Update the kusudb networks table.
a. You can do this through netedit only after deleting the related device record from the nics table and the node-group associtation records for the ng_has_net table. And then, inserting those records back into their respective tables after updating the network configuration.
b. Or, you could simply update the networks table record of your public interface manually.

A DHCP public interface record looks like this:
netid | network | subnet | device | suffix | gateway | options | netname | startip | inc | type .. | usingdhcp
1 ..... | ................ | ............. | eth1 .... | -eth1| ................. | ............... | public .... | ........... | 1 .. | public | t

3.a. In /etc/rc.kusu.d/, move the following python files in the firstrun directory in to the parent directory. These are essentially the kusurc scripts which run only once on the first boot.

S02KusuApache.rc.py
S02KusuDHCPD.rc.py
S02KusuNamed.rc.py

3.b. Run
kusurc S02KusuApache.rc.py
kusurc S02KusuDHCPD.rc.py
kusurc S02KusuGenconfig.rc.py
kusurc S02KusuNamed.rc.py

These will hopefully cover all of the services which will be affected by the change in your public network interface.

You can go ahead and start testing your cluster for inconsistencies from this point.

If you find any inconsistencies, try to find a kusu way of handling the reconfiguration. (i.e.) Try to use the kusurc scripts to reconfigure or if that fails, then try to use genconfig plugins and restart the service and if even that fails, only then manually reconfigure.

Please document your steps here for reference and then if you have any problems, we will be able to better help you.

Good luck!
cheers,
Kunal